I have one. I think of it as being a box containing about 100 musical looping games. You pick one of the games, then you try to make music from it. So the mode becomes your limiting structure, and you play within those boundaries. It's fun, although I'm probably not going to keep it.

----- from userguide-----"There are several operating modes that can be selected. The mode numbersare shown below. More operational details of these modes will be described
in section 5. You can also switch from any mode to reverse mode and/or halfspeed mode during playback using MIDI controls.

Modes 31-40: Automatic Fading of a Loop

Operating modes 31-40 cause the loop playback to fade away over time (...).
The first note starts the initial record process, which continues until theevent count is reached. The number of loops required to completely fade thesignal is determined by the mode number minus 30. Manual layering can be
used in this mode. New layers will start at full volume and then fade overtime like the original loop. This allows interesting effects such ascontinuous layering of new musicpassages. Loop playback can be stopped with
the double press of a footswitch.

Modes 41-50: Automatic Fading of a Loop with Auto LayeringOperating modes 41-50 are the same as the automatic fading modes describedabove,except that automatic layering is used during loop playback as shown
in the figure below. This mode can be used to create feedback delay effects.The number of loops required to completely fade the signal is determined bythe mode number minus 40.This example assumes the footswitch starts the
initial record process, which continues until the event count is reached. Asingle footswitch press will stop playback at the end of the current loop. Adouble footswitch press stops the loop playback immediately.

Modes 61-70: Duplicate Loop During First Layer RecordingA given loop can be duplicated multiple times during the first layerrecording using operating modes 61-70. This can be useful if you have ashort phrase that you want to play back multiple times while you record a
longer phrase over it.The number of repeat times is set by the operatingmode minus 60. If the selected number of duplications exceeds the memorycapacity, then next lower value is used.The example below shows operating
mode 62. After loop playback begins, the first press of a footswitch forlayer recording will duplicate the loop 2 times while a new layer isrecorded on top of it. The display will count down the number ofduplications left while the original loop is played. After this layer
recording is complete, the longer loop will start playing back. From thispoint forward, it acts the same as operating mode 10 in which multipleadditional layers can be recorded with no additional duplication. Once a new
layer has been recorded, the right LED will turn from yellow to green. Thisprocess can be repeated indefinitely. The playback can be stopped at anytime with the double press of the footswitch."----- from userguide end -----

So it seems there's a kind of feedback and a kind of multiply (only onsecond layer).It's no EDP but it's not the same price either. You'd better know in advancethe "structure of the song", you can't change the mode on the fly (except
reverse mode and/or half speed mode).